NEEDS A LOT OF TLC: Insurance titan Joseph Plumeri says his apartment at the old Stanhope Hotel has $3 million in defects. Photo: Getty Images

(Matthew McDermott)

NEEDS A LOT OF TLC: Insurance titan Joseph Plumeri says his apartment at the old Stanhope Hotel has $3 million in defects. (
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This could be the city’s priciest fixer-upper.

Joseph Plumeri’s full-floor apartment across the street from the Metropolitan Museum of Art has five bedrooms, 7 1/2 bathrooms, 10-foot ceilings, sweeping views of Central Park — and about $3 million worth of defects that weren’t discovered until after he bought the place for $20.5 million, the insurance honcho says in a blockbuster suit.

“The defects create a nuisance and/or danger to the 15th-floor apartment residents and others’ life, health and safety,” Plumeri’s holding company says in the $12 million suit against the development company that converted the former Stanhope Hotel into a luxury co-op.

Plumeri, CEO of the insurance-brokerage giant Willis Holdings Group, bought the 8,300-square-foot apartment through the holding company in March 2010, sources said.

He began renovations that fall, when it was found that the apartment and building were “riddled with numerous latent defects, including defective waterproofing, defective installation of floors and soundproofing . . . defective fireproofing, [and] defective structural work,” the suit says.

Other apartments have the same issues, the suit says, and last November, after Plumeri’s costly renovation was finished, the apartment suffered water damage from a leak in the apartment upstairs, which is currently on the market for $27.5 million.

The suit seeks to force the company behind the conversion of the hotel, Extell Development, to pay for the defects in Plumeri’s apartment and for similar repairs in the upstairs pad.

“Disturbing noise is readily discernible in the 15th-floor apartment when people are present in the 16th-floor apartment,” and if it’s occupied without the necessary remediation work, “uncontrolled leaking will occur and cause water damage” to Plumeri’s place, the suit says.

A rep for Extell said the suit “has no merit.”

“Extell prides itself on doing the highest quality work. If there’s an issue that’s brought to our attention, we address it immediately,” the spokesman said.

Plumeri and his lawyer did not return calls for comment.

Plumeri, 68, was a longtime Citigroup exec before taking over Willis, where he reportedly raked in $19 million in 2009 alone. Under his leadership, Willis’ profits have gone through the roof and it obtained the naming rights to the Sears Tower in Chicago, now called Willis Tower.

He is also the owner of the Yankees’ double-A affiliate, the Trenton Thunder.